Pages

18 April 2012

Flavour Journal - Umami Ice Cream

Posted by
DFact

With the release of the International Journal of Gastronomy and Food Science we saw a enormous wealth of information previously reserved for those willing to spend a reasonably large sum of money on The Modernist Cuisine. Admittedly the Journal lacks the packaging and photography that the Modernist Cuisine does, however both hold a wealth of information and one is free and one is not.

We can now add the Flavour Journal, or simply Flavour as it is better known, into that list. Flavour is a peer reviewed, open acccess, online journal that publishes interdisciplinary articles on flavour, its generation and perception, and its influence on behaviour and nutrition.

"We seek articles on the psychophysical, psychological and chemical aspects of flavour as well as those taking brain imaging approaches. We take flavour to be the experience of eating food as mediated through all the senses. Thus we welcome articles that deal with not only taste and aroma, but also chemesthesis, texture and all the senses as they relate to the perception of flavour."

"Flavour emphasises work that investigates the flavour of real foods and encourages contributions not only from the academic community but also from the growing number of chefs and other food professionals who are introducing science into their kitchens, often in collaboration with academic research groups."

Still at a very early stage there are only 5 or 6 articles published at this time, however be sure to keep an eye as this is bound to grow and host some quality content. I've picked out a study below and condensed it to some of the most relevant pieces of information.

You can see all the articles and read any of them in their entirety from the link below.

Use of the term 'umami' for the fifth basic taste and for describing the sensation of deliciousness is finding its way into Western cuisine. The unique molecular mechanism behind umami sensation is now partly understood as an allosteric action of glutamate and certain 5'-ribonucleotides on the umami receptors. Chefs have started using this understanding to create dishes with delicious taste by adding old and new ingredients that enhance umami. In this paper, we take as our starting point the traditional Japanese soup broth dashi as the 'mother' of umami and demonstrate how dashi can be prepared from local, Nordic seaweeds, in particular the large brown seaweed sugar kelp (Saccharina latissima) and the red seaweed dulse (Palmaria palmata), possibly combined with bacon, chicken meat or dried mushrooms to provide synergy in the umami taste. Optimal conditions are determined for dashi extraction from these seaweeds, and the corresponding glutamate, aspartate and alaninate contents are determined quantitatively and compared with Japanese dashi extracted from the brown seaweed konbu (Saccharina japonica). Dulse and dashi from dulse are proposed as promising novel ingredients in the New Nordic Cuisine to infuse a range of different dishes with umami taste, such as ice cream, fresh cheese and bread.

Summary for practical use

The primary stimulatory agent in umami is the chemical compound glutamate, which is found in large amounts in the Japanese seaweed konbu, which is used to prepare the soup broth dashi. We have explored the potential of local Nordic seaweeds, in particular sugar kelp and dulse, for dashi production and have discovered that dulse is high in free glutamate and hence a good candidate for umami flavouring. We describe methods by which to optimise the umami flavour using sous-vide techniques for extraction of the seaweeds, and we demonstrate how dulse dashi can be used in concrete recipes for ice cream, fresh cheese and sourdough bread.

Background

Although umami was suggested as a basic taste in 1908 by the Japanese chemist Kikunae Ikeda[1], umami only caught on very slowly in the Western world [2-5]. Being a verbal construction to describe the essence of delicious taste ('umai' (旨い) is delicious, and 'mi' (味) is essence, inner being or taste), the term 'umami' was coined by Ikeda to signify a unique and savoury taste sensation that should be ranked as the fifth basic taste along with the four classical basic taste modalities: sour, sweet, salty and bitter.

There are several reasons for the slow acceptance of umami as a basic taste in the Western world. First, in contrast to Japanese cuisine, there is no single common ingredient in Western cuisines that provides as clean a sensation of umami as dashi, whereas Western cuisine has kitchen salt (sodium chloride) for salty, ordinary table sugar (sucrose) for sweet, quinine for bitter and acid for sour. Second, cultural differences imply fundamental differences in taste description and codability of taste

Materials and Methods

Sous-vide water extracts from seaweeds

Two types of water were used for seaweed extracts: ordinary tap water (Copenhagen, Denmark; water hardness = 20°dH) and filtered, demineralised soft water. All extractions were based on 10 g of dry seaweed in 500 ml of water placed in a plastic bag sealed under vacuum pressure (sous-vide) at 98.5 kPa in a Komet Plus Vac 20 (KOMET Maschinenfabrik GmbH, Plochingen, Germany) and immersed over a period of 45 minutes in a water bath at the prescribed constant extraction temperature.

Sensory perception

Because the present paper is not intended to be a quantitative study of the sensory perception of umami flavour in the seaweed extracts and the dishes flavoured by the extracts, we have not used a formal panel of professional tasters but employed a subjective and qualitative measure of taste sensation by integrating statements from experimenters and colleague chefs who are very experienced in evaluating and describing taste. The subjective analysis was carried out by a minimum of five qualified chefs who are considered trained tasters. In the case of the dulse ice cream, the tasting was part of a master's degree thesis on the complexity in food (Faculty of Life Sciences, University of Copenhagen, Copenhagen, Denmark) that was favourably received by a tasting panel of 60 persons. In addition, we registered responses from a large number of individual tasters on different occasions when the dulse-infused dishes were presented and tasted.

Amino acid analysis

All chemicals used were from Sigma-Aldrich (Copenhagen, Denmark) and of HPLC quality or better. Amino acid analysis was performed using the Biochrom 31+ Protein Hydrolysate System amino acid analyser (Biochrom, Cambridge, UK). Prior to analysis, proteins were precipitated by addition of trichloroacetic acid, and lipids were extracted with hexane. The amino acids were identified and quantified by comparison with pure amino acid standards with a major focus on glutamic acid, aspartic acid and alanine in their deprotonated states.Examples of dishes flavoured by dulse

Ice cream with dulse

600 g of dulse-infused milk (infuse at 20 g of dulse/litre of milk)

100 g of cream

80 g of trimoline (inverted sugar syrup)

35 g of sugar

24 g of ColdSwell cornstarch (KMC, Brande, Denmark)

Place the dulse and milk in a plastic bag under vacuum and seal, leaving it in a refrigerator overnight to cold-infuse. Strain the dulse and blend it into a fine purée, and preserve to be added later. Dissolve the sugar and trimoline in a small amount of warmed milk. When cooled, add the milk to the rest of the components, mix thoroughly and freeze the mixture in Pacojet containers. Just before serving, the ice cream is prepared in the Pacojet by high-speed precision spinning and thin-layer shaving to produce a creamy consistency of the ice cream.

The dulse ice cream was conceived to demonstrate the culinary versatility of seaweed in an often unexpected fashion. We chose a low-fat base of almost all milk used, allowing the flavour to emerge. Although there was initial reluctance among some tasters to the idea of seaweed ice cream, the vast majority responded with satisfaction upon actually consuming the ice cream.The colour of the dulse ice cream is a very pleasing light mauve. The flavour is delicate, light and floral. Some tasters have compared the dulse ice cream with Japanese green tea ice cream, which is indicative of a nuanced, acceptable flavour profile.

We also observed an improvement in texture of the dulse-infused ice cream, which is creamier and smoother than the same ice recipe without dulse. This change in texture is likely caused by the polysaccharides released from the dulse.